Hydrothermal method for manufacturing a catalytic material useful in preparing catalysts for hydrocarbon conversion processes

ABSTRACT

Hydrothermal conversion method for manufacturing a catalytic material useful in preparing catalysts for hydrocarbon conversion processes, comprising coprecipitating silica and alumina in amorphous form as a hydrogel slurry in the presence of acetate ion, filtering and drying said slurry to produce a hydrogel material, washing said hydrogel material, and subjecting said washed hydrogel material to autoclave conditions of elevated temperature and pressure in a reaction zone until a substantial amount of a layered crystalline clay-type aluminosilicate mineral is formed, preferably in an intimate admixture with a substantial amount of unreacted amorphous cogel comprising silica and alumina, and if desired incorporating in the reaction zone product before or after drying thereof a component comprising a hydrogenating metal.

United States Patent Jaffe [451 May 23, 1972 [54] HYDROTI-IERMAL METHOD FOR MANUFACTURING A CATALYTIC MATERIAL USEFUL IN PREPARING CATALYSTS FOR HYDROCARBON CONVERSION PROCESSES Joseph Jaffe, Berkeley, Calif.

Chevron Research Company, San Francisco, Calif.

[22] Filed: May 20,1970

[Zl] Appl.No.: 39,174

[72] Inventor:

[73] Assignee:

Related U.S. Application Data [63] Continuation-in-part of Ser. No. 763,922, Sept. 30,

[52] U.S. Cl. ..252/455 R, 23/113, 252/453 [51] Int. Cl. ..B0lj 11/40, COlb 38/28 [58] Field of Search ..252/453, 442, 455 R;

[56] References Cited UNITED STATES PATENTS 3,252,757 5/1966 Granquist ..252/455X 3,140,253 7/1964 2,914,464 ll/l959 Plank et al. ..252/455 X Burton et al. ..208/l l l X [5 7] ABSTRACT Hydrothermal conversion method for manufacturing a catalytic material useful in preparing catalysts for hydrocarbon conversion processes, comprising coprecipitating silica and alumina in amorphous form as a hydrogel slurry in the presence of acetate ion, filtering and drying said slurry to produce a hydrogel material, washing said hydrogel material, and subjecting said washed hydrogel material to autoclave conditions of elevated temperature and pressure in a reaction zone until a substantial amount of a layered crystalline claytype aluminosilicate mineral is formed, preferably in an intimate admixture with a substantial amount of unreacted amorphous cogel comprising silica and alumina, and if desired incorporating in the reaction zone product before or after drying thereof a component comprising a hydrogenating metal.

4 Claims, No Drawings HYDROTHERMAL METHOD FOR MANUFACTURING A CATALYTIC MATERIAL USEFUL IN PREPARING CATALYSTS FOR HYDROCARBON CONVERSION PROCESSES RELATED APPLICATION This application is a continuation-in-part of Joseph Jaffe application Ser. No. 763,922, filed Sept. 30, 1968.

INTRODUCTION This application relates to a method for manufacturing a catalytic material useful in preparing hydrocarbon conversion catalysts.

PRIOR ART It is known, particularly from Granquist, U.S. Pat. No. 3,252,757, that a relatively new layered crystalline aluminosilicate clay-type mineral that has been synthesized has the empirical formula nSiO A1 mAB .XHZO where the layer lattices comprise said silica, said B, and where n is from 2.4 to 3.0

m is from 0.2 to 0.6

A is one equivalent of an exchangeable cation having a valence not greater than 2, and is external to the lattice,

B is chosen from the group of negative ions which consists of E, OH, 9&0 and mixtures thereof, and is internal in the lattice, and

x is from 2.0 to 3.5 at 50 percent relative humidity, said mineral being characterized by a d spacing at said humidity within the range which extends from a lower limit of about 10.4 Angstroms to an upper limit of about 12.0 Angstroms when A is monovalent, to about 147 Angstroms when A is divalent, and to a value intermediate between 12.0 Angstroms and 14.7 Angstroms when A includes both monovalent and divalent cations. The equivalent of an exchangeable cation, A, in said mineral, may be chosen from the group consisting of H NH Li K /zCa /Ba and mixtures thereof.

Said synthetic layered crystalline aluminosilicate mineral of said Granquist patent is known from U.S. Pat. No. 3,252,889 to have application in calcined form as a component of a catalytic cracking catalyst, and applications of said layered aluminosilicate in calcined form as a component of a hydrocracking catalyst have been disclosed in copending applications Ser. Nos. 760,619 and 750,038.

Said layered mineral of said Granquist patent is a randomly interstratified montmorillonite-mica, that is, one containing randomly alternating montmorillonite and mica layers. It expands upon glycerol treatment, and irreversibly collapses to a mineralogically different mineral species upon calcination.

OBJECTS In view of the foregoing, it is an object of the present invention to provide a method for manufacturing a catalytic material useful in preparing hydrocarbon conversion catalysts, said material having improved characteristics compared with the mineral of said Granquist patent.

STATEMENT OF INVENTION In accordance with the method of the present invention, there is provided a method for manufacturing a catalytic material useful in preparing catalysts for hydrocarbon conversion processes, which comprises coprecipitating alumina and silica in amorphous form as a hydrogel slurry from an aqueous solution containing compounds of aluminum and siliccon and containing a compound comprising acetate ion, said coprecipitating being accomplished at a pH of 5.5 to 8 in the presence of said acetate ion, filtering and drying said slurry to produce a dried hydrogel material, washing said dried hydrogel material, forming a second hydrogel slurry comprissaid alumina, and

ing said washed hydrogel material, subjecting said second hydrogel slurry to autoclave conditions of elevated temperature and pressure in a reaction zone until a substantial amount of a layered crystalline clay-type aluminosilicate mineral forms in an intimate admixture with unreacted hydrogel, and drying said admixture to form said catalytic material. A component comprising a hydrogenating metal may be incorporated in said intimate admixture before or after drying thereof, and the resulting composite may be dried and calcined to produce a hydrocarbon conversion catalyst useful in hydrogenative processes. Said hydrogel material preferably is present in said second hydrogel slurry in an amount of 5 to 50 weight percent, preferably 5 to 25 weight percent. Preferably a compound of fluorine will be present in the final catalytic material, as a result of the presence of a compound of fluorine in said second hydrogel slurry. Preferably the elevated temperature is in the range 170 to 350 C. The desired quantity of crystalline mineral formed preferably is that quantity which will result in 5 to weight percent thereof, preferably 20 to 70 weight percent thereof, conversion zone product. Said conversion zone product, when it comprises said crystalline mineral in intimate admixture with unreacted amorphous silica-alumina cogel, will have a surface area of 200 to 380 Mlg.

The synthetic layered crystalline clay-type aluminosilicate mineral that is formed by crystallization during the process of the present invention preferably has a silica/alumina ratio above 3.0 When that mineral, or the reaction zone product referred to herein comprising said mineral and unreacted amorphous cogel, is combined with a hydrogenating component, and the resulting composite is dried and calcined, the d spacing of said mineral may be different than it was prior to drying and calcining. However, said mineral, prior to drying and calcining, preferably has the following formula:

nSiO A1 0 mAB x11 0, where the layer lattices comprise said silica, said alumina, and said B, and where n is more than 3.0

m is from 0.2 to 0.6

A is one equivalent of an exchangeable cation having a valence not greater than 2, and is external to the lattice,

B is chosen from the group of negative ions which consists of F, OH21 A0" and mixtures thereof, and is internal in the lattice, and

x is from 2.0 to 3.5 at 50 percent relative humidity, said mineral being characterized by a d spacing at said humidity which is between 10.25 Angstroms and 10.4 Angstroms when A is monovalent. The equivalent of an exchangeable cation, A, in said mineral may be chosen from the group consisting of H*, NHJ, Li Ki fica Mg. SF', and 68a, and mixtures thereof.

Preferably the hydrogel or hydrogel slurry is washed with dilute ammonium acetate and water before being subjected to the elevated temperature and pressure treatment of the process of the present invention.

The hydrogel or hydrogel slurry may be prepared in any convenient manner, using suitable precursor compounds of the final components of the desired catalyst, and observing the silica/alumina ratios specified herein. A suitable general procedure for forming the hydrogel or hydrogel slurry may be found in Joseph Jaffe, U.S. Pat. No. 3,280,040. Aluminumcontaining precursor compounds preferably are chlorides. Suitable silicon-containing precursor compounds are alkali metal silicates.

Said component comprising a hydrogenating metal may be a hydrogenating component precursor compound, preferably selected from compounds of nickel, cobalt, platinum, palladium and rheniuml Said precursor compound preferably is a salt, for example a chloride or nitrate. In addition to combining the reaction zone product with said precursor compound, said reaction zone product advantageously may be combined with a catalytic hydrogenating component precursor compound selected from compounds of tungsten, molybdenum, tin and zinc.

Any one or more of the elements contained in the aforementioned catalytic hydrogenating component precursors may be present in any desired final hydroprocessing catalyst, in the form of metals, oxides, sulfides or any combination thereof, in amounts selected from the following list, based on the total catalyst, calculated as metals:

Element Weight Percent Ni or Co 1 20 Pt or Pd 0.01 2.0

W or Mo 5 35 it has been found that the presence of tin, in the metal, oxide or sulfide form, particularly in combination with nickel, in a hydroprocessing catalyst manufactured according to the present invention, results in higher hydrocracking activity and higher hydrogenation activity than would be exhibited by a catalyst that is identical except that contains no tin. Further, the presence of tin permits the hydrogenation activity to be controlled in an essentially reversible manner by varying the amount of sulfur present in the feed.

Particularly effective hydrogenating components and combinations of catalytic hydrogenating components in any desired hydroprocessing catalyst, in the form of metals, oxides or sulfides, are:

Ni or C0 NiMo or CoMo NiSn PtRe Pt or Pd NiW or CoW MoZn PdRe Re Said second hydrogel slurry additionally may contain precursor compounds of an oxide selected from titania, zirconia, hafnia, thoria and ceria; any one or more of these oxides may be present in the final catalyst in an amount of 0 to 30 weight percent.

Said second hydrogel slurry should contain fluorine or a compound of fluorine, in an amount which will provide fluorine or a compound of fluorine in the final catalytic material in an amount of 0.1-3 weight percent, preferably 0.5-3 weight percent, more preferably 0.5-2 weight percent, calculated as F.

Because the suitable hydrothermal conversion temperatures for forming the desired synthetic crystalline mineral from precursors thereof lie far above the normal boiling point of water, said second hydrogel slurry conveniently is subjected to said conditions at elevated temperature and pressure in a pressure vessel, so that the water contained therein will remain in the liquid state by autoclave action. The hydrogel slurry is maintained at the selected temperature and pressure for a sufficient period of time for the formation of the desired crystalline aluminosilicate to the desired extent. Preferred temperatures are 340 to 700 F., at pressures above 500 psig, preferably above 900 psig. The temperatures at which the formation of the desired crystalline aluminosilicate takes place is in the practical range 530 to 700 F., with about 545 F. being optimum. The optimum temperature does not vary greatly with the presence in said second hydrogel slurry of such final optional catalyst components as titania and zirconia. The pressure need not be appreciably in excess of the autoclave pressure of the hydrogel or hydrogel slurry, i.e., that developed by the vapor pressure of the water itself. The latter is only negligibly changed by the dissolved material in said second hydrogel slurry, because the bulk of the solids therein is not in a form which appreciably changes the vapor pressure. Therefore, the ordinary tabulations of steam pressure may be used. Accordingly, at 545 F. the pressure developed is around 1000 sig. p The reaction time may vary from 0.1 to 100 hours, depending upon the reaction temperature, pressure and degree of conversion of said second hydrogel slurry to said clay-type aluminosilicate that is desired. With lower reaction temperatures longer reaction times are required for a given degree of conversion, and vice versa. Preferably a reaction time of 0.2 to 5 hours, more preferably 0.2 to 2 hours, is used.

When said second hydrogel slurry has remained at the selected conditions of temperature and pressure for a suffcient time for the desired amount of the desired crystalline aluminosilicate to form, the mixture is allowed to cool, and the slurry containing said crystalline aluminosilicate is dried, for example at 200450 F. Thereafter, the dried material may be combined prior to or after calcining with any desired hydrogenation component or components to produce a hydroprocessing catalyst. The hydroprocessing catalyst so produced preferably is activated in an oxygen'containing gas stream, which may be air, at a temperature of 900 to 1 F. for 0.5 to 20 hours, to produce the final solid catalyst. It has been found that optimum activity is developed in the catalyst if the activation temperature does not exceed 1 1 50 F.

The hydroprocessing catalyst produced as described above may be used in such reactions as hydrofining and hydrocracking. Those skilled in the art will recognize which catalytic components the catalyst should contain for the particular reaction for which the catalyst will be used, and will be aware of the operating conditions at which the reaction should be conducted.

The reaction zone product produced in the manner described above, either before or after addition thereto of a hydrogenating component, may be broken into particles, for example pulverized into a powder, and said particles may be dispersed in a hydrogel or hydrogel slurry comprising components selected from precursor compounds of alumina, silica, silica-alumina, silica-alumina-titania, and silica-aluminazirconia, and the resulting mixture may be dried and activated, at the same conditions used for drying and activating the material of said particles, to form a catalyst composite material. The hydrogel or hydrogel slurry in which said particles are dispersed may contain any or all of the components of the hydrogel or hydrogel slurry used in making said particles, or may contain any components that the foregoing discussion indicates could have been contained in the hydrogel or hydrogel slurry used in making said particles. Additionally, the hydrogel or hydrogel slurry in which said particles are dispersed may contain particles of crystalline zeolitic molecular sieve, preferably X" or Y" type. Said molecular sieve desirably may be an ultra-stable molecular sieve, that is, one having a sodium content below 3 weight percent, calculated as Na 0, a unit cell size below about 24.65 Angstroms, and a silica/alumina ratio above about 2.15.

EXAMPLES The following examples will aid in understanding the catalyst preparation method of the present invention, and use of the catalyst prepared thereby.

EXAMPLE I A hydrocarbon conversion catalyst cracking component, comprising a novel synthetic layered crystalline material in an intimate admixture with unreacted silica-alumina cogel, is prepared from an amorphous cogelled precursor material of the following composition:

Wt. of Total Cogelled Weight Molar Component Material, Anhydrous Basis Ratio Ratio 2 67 M A1 0 33 1 l The amorphous cogelled precursor material is prepared by the following steps, using sufficient quantities of the starting materials to produce the above-indicated weight percentages of the components of said cogelled precursor material.

1. An aqueous acidic solution is prepared, containing AlCl and acetic acid.

2. A dilute sodium silicate solution is added to said acidic solution to form a clear dispersion of colloidal silica in AlCl and acetic acid.

3. An ammonium hydroxide solution is added to said clear dispersion to precipitate alumina and silica in the form of a hydrogel slurry, at a pH of 7-8.

4. Ammonium bifluoride is added to said hydrogel slurry, in an amount sufficient to provide 0.1 to 3 weight percent fluoride in said hydrogel slurry, calculated as F, based on the silica and alumina in said hydrogel slurry. Instead of ammonium bifluoride, sodium fluoride or HF may be used in preparation of the material of the present invention.

5. The slurry is filtered to produce a hydrogel filter cake. The filter cake is partially dried to about 25 percent solids content and is extruded into small pellets. The pellets are washed repeatedly with dilute ammonium acetate solution to remove sodium and chloride ionic impurities.

A slurry is formed from the washed hydrogel pellets and water, using sufficient water to provide a slurry solids content of wt. percent. The slurry is loaded into an autoclave and there is aged for 0.5 to 2 hours at 1,400 psig autogenous pressure (300 C.), resulting in a slurry containing a crystallized mineral, fluorine, and unreacted amorphous cogel, all in intimate admixture.

The autoclaved slurry is dried. X-ray diffraction and other examinations of the resulting material indicate the presence of unreacted amorphous cogel, fluorine, and a synthetic layered crystalline clay type aluminosilicate, consisting predominantly of mica-like layers, all in intimate admixture. Upon treatment with glycerol the material does not swell, as does said Granquist synthetic aluminosilicate material.

EXAMPLE 2 A portion of the material of Example 1 is pulverized, moistened with a solution of palladium ammino nitrate and chromium nitrate, extruded into lainch-diameter pellets, dried and calcined to form a hydrocracking catalyst containing 0.5 weight percent palladium and 0.5 weight percent chromium. Said catalyst is used to hydrocrack a hydrofined California gas oil of the following description:

Gravity, "API 34 Aniline point, F. [93 Organic nitrogen, p.p.m. 0.] Boiling range, F. 550-850 The hydrocracking conditions are as follows:

Liquid hourly space velocity, V/V/hr. 2.0 Per-pass conversion to products boiling below 400F., vol.% 60 Exit gas rate, SCF/bbl. 5600 Total pressure, p.s.i.gv i200 The starting temperature necessary to achieve the indicated per-pass conversion is 580 F. The catalyst fouling rate is 0.025 F. per hour.

What is claimed is:

l. A method for manufacturing a catalytic material useful in preparing catalysts for hydrocarbon conversion processes, which comprises coprecipitating alumina and silica in amorphous form as a hydrogel slurry from an aqueous solution containing compounds of aluminum and silicon and containing a compound comprising acetate ion, said coprecipitating being accomplished at a pH of 5.5 to 8 in the presence of said acetate ion, filtering and drying said slurry to produce a dried hydrogel material, washing said dried hydrogel material, forming a second hydrogel slurry comprising said washed hydrogel material, subjecting said second hydrogel slurry to autoclave conditions of elevated temperature and pressure in a reaction zone until a substantial amount of a layered crystalline claytype aluminosilicate mineral forms in an intimate admixture with unreacted hydrogel, said aluminosilicate mineral prior to drying and calcining having the formula nSi0 A1 0 mAB x11 0, where the layer lattices comprise said silica, said alumina, and said B, and where n is more than 3.0

m is from 0.2 to 0.6 A is one equivalent of an exchangeable cation having a valence not greater than 2, and is external to the lattice,

B is chosen from the group of negative ions which consists of F, OH, &0 Oand mixtures thereof, and is internal in the lattice, and

x is from 2.0 to 3.5 at 50 percent relative humidity, said mineral being characterized by a d spacing at said humidity which is between 10.25 Angstroms and 10.4 Angstroms when A is monovalent, and drying said admixture to form said catalytic material.

2. The method as in claim 1, wherein a compound of fluorine is present in said second hydrogel slurry.

3, The method as in claim 1, with the additional steps of incorporating in said intimate admixture a component comprising a hydrogenating metal, and drying and calcining the resulting composite to produce a catalyst.

4. The method as in claim 3, wherein said intimate admixture is dried before incorporation therein of said component comprising a hydrogenating metal. 

2. The method as in claim 1, wherein a compound of fluorine is present in said second hydrogel slurry.
 3. The method as in claim 1, with the additional steps of incorporating in said intimate admixture a component comprising a hydrogenating metal, and drying and calcining the resulting composite to produce a catalyst.
 4. The method as in claim 3, wherein said intimate admixture is dried before incorporation therein of said component comprising a hydrogenating metal. 